Steady bearing for centrifugal separators



Jan. 21, 1936.

J. Fl THOLL STEADY BEARING FOR CENTRIFUGAL SEPARATORS Filed Aug. 30, 1932 2 Sheets-Sheet" 1 Jan. 21-, 136. J THQLL 2,028,730

STEADY BEARING FOR CENTRIFUGAL SEPARATORS Filed Aug 30, 1952 2 Sheets-Sheet 2 F592 I y. 3

INVENTO Patented Jan. 21, 1936 UNITED STATES STEADY BEARING FOR GENTRIFUGAL SEPARATORS John F. Tholl, Needham, Mass., assignor to American Tool and Machine Company, Hyde Park, Mass, a corporation of Massachusetts Application August 30 5 Claims.

This invention relates to centrifugal separators and is more especially concerned with centrifugals of the suspended type.

Such machines are much used in the sugar in- 5 dustry and in other lines, especially in connection with extracting, washing and refining operations. In using these machines it is a common practice to unload or discharge the material collected on the inside of the revolving basket by means of a scraper which is forced laterally into the wall of solid material and is then traversed in a direction parallel to the lining of the basket, this movement cooperating with the rotary motion of the basket to dislodge the accumulated solids and to cause them to drop through the bottom of the basket. The flexible mounting or support for suspended centrifugals introduces difficulties in performing the discharging operation in this manner, particularly when the material to be unloaded is packed fairly hard, because the laterally directed pressure of the scraper in entering this wall of material deflects the revolving basket, thus causing unusual strain on the entire mechanism and tending to produce violent vibratory movements of the basket.

The present invention deals especially with these conditions and it aims to devise a thoroughly practical solution for them.

The nature of the invention will be readily understood from the following description when read in connection with the accompanying drawings, and. the novel features will be particularly pointed out in the appended claims.

In the drawings,

Figure 1 is a vertical, sectional view of a suspended centrifugal constructed in accordance with this invention; 7 7

Figs. 2 and 3 are side views illustrating, on a larger scale, certain details of the construction shown in Fig. 1, some of the parts in Fig. 2 being shown in section; and

Fig. 4 is a view similar to Fig. 2 illustrating a modification.

Fig. 1 shows the invention as applied to the machine known commercially as the Weston centrifugal which has been on the market for many years. This machine includes a basket 2 mounted to rotate in the usual curb or casing 3, the basket being suspended from overhead by means of an inside spindle 4 which is hung on a ball 5 mounted in the supporting bracket 6. The usual spider at the bottom of the basket is bolted to the lower end of an outside spindle I carrying a pulley 8 at its upper end by means of which the spindle may be belted to any convenient source of power.

, 1932, Serial No. 631,074

The weight of the basket and its load is transmitted to the inside spindle through a step bearing ID of an anti-friction type, and the lower end of this bearing is enclosed in a cup [2 which is bolted to the outside spindle and which holds a quantity of oil or other lubricant in contact with thebearing.

All of these parts are constructed, arranged and operated in the usual manner except that the usual cup at the bottom of the step bearing has been replaced by a special cup, best shown in Fig. 2, which is provided with a short downwardly extending shaft I3 co-axial with the spindles 4 and 1. This shaft revolves in a bearing bushing It carried by a collar iii to which one end of a laterally extending arm [6 is secured. The opposite end of this arm extends through and is free to slide in a bracket I1 which is secured rigidly to the curb or casing 3 of the machine, as will be evident from an inspection of Figs. 1 and 3. An

upright rod l8 having a handle 20 secured to its upper end is threaded through the bracket in such a manner that its lower end can be made to bear on the flattened end of the rod I6 to clamp this rod securely to the machine frame or casing. Preferably the arrangement is such that only a partial rotation of the rod [8 is required to clamp or release the arm [6.

With this arrangement the machine may be operated in the usual manner and with no change whatever in results until the unloading or discharging operation is begun, the rod l8 being slightly raised so as to leave the arm 16 free during all of this time. Consequently, the bearing for the shaft I 3 is free to swing or to gyrate in a horizontal plane and will follow any gyratory or swaying movements of the axis around which the basket revolves. Immediately prior to performing the discharging operation, however, the handle 20 is turned to clamp the rod IE to the stationary bracket I1. Usually the basket is running smoothly at this time so that this clamping movement simply locks the lower bearing l5 in position to steady the spindle I and the basket while they continue to revolve normally. When the scraper or discharger is pressed laterally against the wall of solid material accumulated on the lining of the basket, it is entered in this material more easily because of the fact that the lower end of the spindle l is steadied by the supplemental bearing mechanism located below the basket. At the same time this mechanism also prevents any substantial deflection of the spindle due to the lateral thrust of the discharger or unloader, and therefore prevents the After the unloading operation has been completed the handle 2!] is given a partial turn to raise the rod l8 and thus release the arm 66.

When so released the lower bearing is entirely freetc movewith'the axis of. rotation of the basket so that the machine will operate exactly as though themechanism provided by this in:

vention were ,not present; 7 Furthermore, the change into either a locked or released condition can be produced instantly and without interfering in any way with the normal operation of the machine. r

In some cases it is found desirable to provide means for cushioning vibrations of the sha'ftl3 .when the arm I6 is locked in its relatively stationary position. 'This may conveniently be done by interpcsing a rubber bushing or rubber seg- .ments between the bearing bushing M and the collar !6. Such a construction is illustrated in .Fig 4 in which the collar [5. is like the collar 65 except that it is made somewhat larger and "it is counter-bored to receive a rubber bushing 28 which encircles the bearing bushing M. The

rubber bushing is held against any substantial 7 vertical displacement by means, of an inwardly ket is free to find its own axis of rotation whenrunning in a normal manner. 7

While I have herein shown and described a V with a. basket and means supported at a point projecting upper flange on a collar ibiand an i outwardly projecting lower flange on thebearing bushing l4. I 1

Itwill .now be appreciated that this invention .provides an exceedingly simple, reliable, and easily operated arrangement for steadying the basket during the unloading operation. At the same time the arrangement is such that the baspreferred embodiment of my invention, it will be evident that the invention maybe embodied in other forms without departing from the spirit or scope thereof.

Having thus described ,my invention, what I desire to claim as new is:

.1. In a centrifugal separator, the combination above the basket for suspendingv the basket for rapid rotation about an approximately vertical axis, of a shaft extending downwardly from said I basket, a bearingfor said shaft located below said basket and mounted to swing in a horizontal plane with. said shaft, an arm connected with said bearingand extending laterally therefrom, astationary guide into which said arm projects, and means for clamping said arm" to said guide. 7 1 7 2. In a; centrifugal separator, the combination with a basket and means supported at a point above the basket for suspending the basket for rapid rotation about an approximately vertical axis, of a shaft extending downwardly from said basket, a bearing for said shaft located below.

said basket and mounted toswing'in a horizontal plane withsaid shaft, an arm connected with said bearing and extending laterally therefrom toward the frame ,of the machine, a bracket secured to said frame and having a guideway in which said arm slides, and a rod threaded through said bracket to bear on saidarm for clamping it to the bracket.

3. In a centrifugal separator, the combination with a basket and means for suspending the basket "for'rapid rotation about an approxima'tely vertical axisfof a shaft extending downwardly 2 from said basket, a bearing for said shaft 10- eated below said basket and mounted to swing normally in a horizontal plane with said shaft, means associated with said bearing for cushioning said swinging movementand means operable a't'the'w ill of the attendant for locking said bearing in position to control 'saidswinging move -ment without disturbing said cushioning action. 7

4. In a centrifugal separator of the type in which the basket is suspended for rapid" rotation aboutan approximately vertical axis, the combination of a shaft extending "downwardly "from said basket, a bearing for said shaft'located below said basket and mounted to swing in a hori:

zontal plane with said shaft, an arm connected,

with said bearing and extending laterally therefrom, and means for locking said arm "in'position to steady said bearing, said means being instantly releasable to unlock the arm.

5. In a centrifugal separator of the type inwhich the basket is "suspended for rapid rotation about'an approximately vertical axis, the combination of a shaft extending downwardly from said basket, a bearing for said shaft located below said basket and mounted to swing in a horizontal plane with 'said shaft, an arm connected with said bearing and extending laterally therefrom, and means for locking-said arm in position to steady said bearing, said'means including a single control element operable to lockor re-- lease the arm instantly while the machine con tinues in operation.

JOHN 'F. mom 

